Let g be the number of grandchildren, and d be the number of dogs. They both have only one head, so the number of heads is

Grandchildren have 2 legs, while dogs have 4. So, the total number of legs is

From the first equation (the one for the heads) we can derive

Substitute this into the second to get

So, there are 9 dogs and (from the first equation

The question is asking to find the variance for the said samples in the problem ans use the sample data to determine each variance, and base on my further computation and further calculation, I would say that the answer would be the following:
#1. 3.3 -> 1 and 3 -> 2/9
#2. 1-> 0->3/9
#3. 6.3 - > 8 and 3-> 2/9
#4 49-> 1 and 8-> 2/9
Y=2x+1
x+y=7
x+(2x+1) =7
3x+1=7
-1 -1
3x=6
x=2------------> Y=2x+1
y=2(2)+1
y=5
X=2
Y=5
Y=2x+4
To graph this linear function, put a point on (0,4) since 4 is the y-intercept. From that point, place the next point two units up and one unit over from the y-intercept since the slope is 2 or 2/1.